Interchangeable tooth and backing for bridgework



D. S. HIGHKIN.

INTERCHANGEABLE TOOTH AND BACKING FOR BBIDGEWORK. APPLICATION man AUG. 12, 1920.

Patented Nov. 2, 1920.

6H0: neg

UNITED STATES arser orricu.

DAVID S. HIGHKIN, OF BALTIMORE, MARYLAND.

INTERCI-IANGEABDE TOOTH. AND BACKING FOR BRIDGEWORK.

Application filed August 12, 1920. Serial No. 403,058.

To all whom it may concern:

Be it known that l, Davin S. HIGHKIN, a citizen of the United States, residing at Bah timore and State of Maryland, have invented certain new and useful Improvements in Interchangeable Teeth and Backlngs for Bridgework, of which the following is a specification.

The present invention relates to tooth structure for making up dental bridgework and is in the nature of an improvement on the prior Patents Nos. 133%,798 and 1,348,799, granted to me on August 3, 1920.

The object of the present invention is to provide a novel and effective structure whereby the tooth facing is simplified, pro viding flat surfaces that may be more easily and accurately ground, with effective means for supporting the facing by and retaining it in the backing, said means also serving as a reinforcement to the backing.

In the accompanying drawings Figure 1 is a perspective view of a tooth structure embodying the present invention.

Fig. 2 is a perspective view of the facing element.

Fig. 3 is a perspective view of the backing element.

Fig. t is a vertical sectional view through Fig. 1, at one side of the retaining pin.

Fig. 5 is a similar view but intersecting the retaining pin.

In the structure disclosed the backing element is preferably of the usual material, gold, comprising a body having a bottom wall 6 and opposite side walls 7 and 8, forming a socket that opens through the front of the element and through its outer end. The front margins of the side walls 7 and 8 are slightly out-turned, forming flanges 9, and the said two side walls 7 and 8 are connected adjacent to said flanges 9 by an upstanding rib or flange 10 that rises from the bottom 6 and terminates short of the top edges of the walls 7 and 8. Projecting from the said rib or flange 10 is a centrally disposed upstanding retaining pin 11.

The tooth or facing element consists of a front portion 12, having the usual buccal surface corresponding to the natural tooth configuration. Tt is provided with an integral rear extension 13, the upper face of which corresponds in form and appearance to the natural tooth configuration. The lower portion of this rear extension tapers clownwardly and is sufficiently thick to properly reinforce the outer or biting face and is adapted to fit between the side walls 7 and 8. It is thus boxed and protected thereby. The said rearwardly extending portion contiguous to its junction with the part 13 is provided with a transverse upwardly extending groove l t that receives the rib or flange l0 and it is furthermore provided with a socket 15 opening into the bottom of the groove and receiving the retaining pin 11. It will be noted that the front portion 12 of the facing is slightly wider than the rearwardly extending portion 13. This provides flanges 16 extending across said rearward portion 13 and abutted against the rear face of the flanges 16 are the flanges'9 of the backing.

With this construction it will be clear that the porcelain facing element is protected and supported by the backing element. Moreover said facing element is provided with flat faces that can be readily ground to fit any particular backing so that the construction can be easily adapted to difierent conditions met with. The rib or flange 10 constitutes a support and bearing for the facing that will effectively resist any tendency of the latter to move with respect to the backing under strains incident to its use. The pin constitutes means whereby the facing can be retained in position, the usual cement being employed for this purpose, and the pin being roughened or smooth as desired.

From the foregoing it is thought that the construction operation and many advantages of the herein described invention will be apparent to those skilled in the art without further description and it will be understood that various changes in the size, shape, proportion and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

What I claim is 1. An interchangeable tooth and backing for bridgework, comprising a backing element having a socket opening through its front face and outer end, and a facing element having a rearwardly extending integral portion that fits in the socket and has an outer biting face exposed at the outer end of the backingyone of said elements being pr0- vided with a transverse flange substantially the Width of the socket and the other element having a transverse groove that receives the flange, one of said elements furthermore having a retaining pin and the other having a socket to receive the pin.

2. An interchangeable tooth and backing for bridgework, comprising a backing element having a socket opening "through its front face and outer end, a flange extending across the socket and a retaining pin that projects from the flange, and a facing element having a rearwardly extending integral portion that fits in the socket and has an outer biting face exposed at the outer end of the backing, said portion having a transverse groove that receives the flange and also having a socket openinginto said groove and receiving the retaining pin.

3. An artificial tooth facing element having a rearWardly extending integral portion provided. With an outer biting surface, said portion having a transverse groove in its rear side and also having a socket opening into said groove.

4. A backing element for artificial tooth facings, having a socket opening through its front face and its outer end, a flange extending across the socket, and a retaining pin projecting from the flange.

In testimony whereof I aflixmy signature.

DAVID S. HIGHKIN. 

